Organochlorine isotopic pattern-enhanced detection and quantification of triclosan and its metabolites in human serum by ultra-high-performance liquid chromatography/quadrupole time-of-flight/mass spectrometry
Article first published online: 15 DEC 2011
Copyright © 2011 John Wiley & Sons, Ltd.
Rapid Communications in Mass Spectrometry
Volume 26, Issue 2, pages 123–132, 30 January 2012
How to Cite
Wu, J.-l., Leung, K.-F., Tong, S.-F. and Lam, C.-W. (2012), Organochlorine isotopic pattern-enhanced detection and quantification of triclosan and its metabolites in human serum by ultra-high-performance liquid chromatography/quadrupole time-of-flight/mass spectrometry. Rapid Commun. Mass Spectrom., 26: 123–132. doi: 10.1002/rcm.5303
- Issue published online: 5 DEC 2011
- Article first published online: 15 DEC 2011
- Manuscript Accepted: 17 OCT 2011
- Manuscript Revised: 14 OCT 2011
- Manuscript Received: 18 AUG 2011
Organochlorines possess special isotopic patterns that obey the chlorine rule. In the case of triclosan (TCS), which contains three chlorine atoms, the isotopic patterns are composed of seven obvious peaks with the calculated masses ranging from 286.9435 to 292.9350 in negative ion mode and with specific isotopic abundance ratios of 100:13.1:97.1:12.6:31.8:4.1:3.6. In this study, mass differences between the calculated and observed m/z values for all isotopic peaks of TCS were less than 3.5 ppm in the analyses of the serum samples by ultra-high-performance liquid chromatography/quadrupole time-of-flight/mass spectrometry (UHPLC-Q-TOF/MS). Combining the characteristics described above, four metabolites were identified as sulfonated TCS, glucuronidated TCS and hydroxylated sulfonated TCS. Several novel MS techniques were applied to improve the sensitivity of quantification of TCS. The limit of detection for TCS in a 250 μL serum sample was 0.05 ng/mL, which was over twenty times lower than values obtained by the LC/triple quadrupole-MS/MS method reported in the literature. The concentration of total TCS (free and conjugated) was quantified to range from 0.15 to 217 ng/mL, whereas free TCS ranged from 0.15 to 10 ng/mL. To the best of our knowledge, this is the first report on the identification of TCS and metabolites in human serum, and it also provides the most sensitive LC/MS approach for the quantification of TCS. Copyright © 2011 John Wiley & Sons, Ltd.